Question

I have a NSDictionary with some parameters I want to display in a UITextField. but

firstname.text = [userdata objectForKey:@"firstname"];

throws an exeption. If I use NSLog on [userdata objectForKey:@"firstname"]; it shows the right value.

This is the thrown exception:

2012-07-05 15:55:56.533 Project[13642:f803] -[__NSArrayM
_isNaturallyRTL]: unrecognized selector sent to instance 0x68c4e20 2012-07-05 15:55:56.534 Project[13642:f803] *** Terminating app due to
uncaught exception ‘NSInvalidArgumentException’, reason: ‘-[__NSArrayM
_isNaturallyRTL]: unrecognized selector sent to instance 0x68c4e20’

If I use

firstname.text = [NSString stringWithFormat:@"%@",[userdata objectForKey:@"firstname"]];

it works, but it puts the values in brackets.
What seems to be the problem here? And why doesn’t the first attempt work?

Answer 1

_isNaturallyRTL

is an undocumented NSString method. It seems that

[userdata objectForKey:@"firstname"]

is an NSMutableArray (guessed from class name), which you’re trying to use as a string. When you use a format string with the %@ format specifier, it calls the -description method of the object to be formatted/printed (so does NSLog), and the description of an NSArray is an NSString that looks like

[ "description of first element", "description of second element" ]

etc., that’s why it puts your text in brackets but doesn’t crash.

All in all, use

[[userdata objectForKey:@"firstname"] objectAtIndex:0]

instead.